1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.Copyright 2002 Society of Automotive Engineers, Inc.All rights reserved. No part of this
3、 publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (
4、outside USA)Fax: 724-776-0790Email: custsvcsae.orgSAE WEB ADDRESS: http:/www.sae.orgAEROSPACE MATERIAL SPECIFICATIONAMS 2451/12Issued DEC 2002Plating, Brush, Tin1. SCOPE:1.1 Purpose: This specification covers the engineering requirements and process for brush plating of tin by electrodeposition. It
5、shall be used, in conjunction with AMS 2451, for general-purpose tin deposits.1.2 Application: This process has been used typically to prevent galling or seizing of metal surfaces, to provide a surface for soft soldering, or to improve corrosion resistance, but usage is not limited to such applicati
6、ons.1.3 Safety - Hazardous Materials: See AMS 2451.2. APPLICABLE DOCUMENTS: See AMS 2451.3. TECHNICAL REQUIREMENTS: The requirements of AMS 2451 shall apply as herein amended.3.1 Procedure: 3.1.1 Except as required in 3.1.1.1 or 3.1.2, tin shall be electroplated directly on the basis metal from a su
7、itable brush plating solution in accordance with processing instructions from the solution manufacturer.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-AMS 2451/12 SAE AMS 2451/12- 2 -3.1.1.1 For alumi
8、num and aluminum alloys, a zinc immersion preplate may be used.3.1.2 Prior to electrodeposition of tin for solderability on aluminum or copper-zinc alloy parts, a copper plate shall be deposited to a thickness of 0.0002 to 0.0003 inch (5.1 to 7.6 m).3.2 Properties: 3.2.1 Thickness: Where “tin flash”
9、 is specified, plate thickness shall be approximately 0.0001 inch (2.5 m).3.3 Solderability: When specified, solderability of the plating shall be in accordance with ASTM B 545. The method of test shall be as specified by purchaser.3.4 Continuity of Plating: When specified, plating on ferrous parts,
10、 having a plating thickness of 0.0004 inch (10 m) or more, shall be subjected to the porosity test of ASTM B 545 and the result evaluated according to the procedure described. When specified, plating on copper and copper alloys shall be subjected to the porosity test for copper basis metal given in
11、ASTM B 545: the specimens shall be considered to have failed if pores in the coating blacken by the polysulfide test.4. QUALITY ASSURANCE PROVISIONS: See AMS 2451.5. PREPARATION FOR DELIVERY: See AMS 2451.6. ACKNOWLEDGEMENT: See AMS 2451.7. REJECTIONS: See AMS 2451.8. NOTES: The requirements of AMS
12、2451 shall apply as herein amended.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-AMS 2451/12 SAE AMS 2451/12- 3 -8.1 When using tin plating for electronics and precision moving parts applications, th
13、e potential for formation of tin whiskers should be considered. Under certain circumstances, metal whiskers grow from surfaces of tin electrodeposits. The tin whiskers are electrically conductive and some have measured 40 to 80 millionths of an inch in diameter with lengths up to 0.375 inch. Whisker
14、s can reduce the electrical resistance between surfaces or cause short circuits. In the case of precision moving parts, displaced whiskers can cause mechanical interference.8.2 Plating thickness greater than 0.0003 inch (8 m) may result in tearing and dewetting during reflow.8.3 The plating meeting
15、the requirements of this specification will exhibit equivalent properties to plating produced in accordance with MIL-T-10727 and AMS 2408.8.4 Key Words: Selective plating, brush plating, tin deposit, corrosion resistance, solderability, gallingPREPARED UNDER THE JURISDICTION OF AMS COMMITTEE “B”Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-
